A very special group of payloads have arrived in French Guiana as the pace
of preparations pick up for the upcoming Flight 165 with an Ariane 5 G
launch vehicle.

The payloads are five small satellites that will accompany Flight 165's
main spacecraft: the French Helios II military reconnaissance/surveillance
platform. This launch will mark the first time a total of six passengers are
carried on a single Ariane 5 mission.

One portion of the supplemental payloads on Flight 165 is composed of four
microsatellites developed by the French defense procurement agency (DGA).
Once in orbit, these spacecraft will form a demonstrator system called
Essaim (the French word for "swarm"), which is to validate technologies for
a future space-based electronic intelligence (ELINT) system.

The other supplemental payload element is a single satellite from the French
CNES national space agency. Called Parasol, the satellite will provide
scientists with a better understanding of Earth's climatic system by
studying the impact of aerosols and how they interact with clouds.

The Parasol designation is an acronym created from its longish name:
Polarization and Anisotropy of Reflectances for Atmospheric Sciences coupled
with Observations from a Lidar. Parasol also is the French word for
"sunshade."

Parasol ultimately will operate in formation with five other civilian
satellites to observe atmospheric phenomena within minutes of each other,
allowing different physical characteristics to be observed. Two of these
complementary satellites already are in orbit (Aqua and Aura, from America's
National Aeronautics and Space Administration), while the remaining three
(Calipso, CloudSat and OCO) will be orbited beginning next year.

Forming a satellite "chain," the five spacecraft will trail each other by
minutes or seconds as they pass a specific point in their orbit, with a
total of 15 minutes separating the lead satellite and the last one in the
lineup.

Parasol and the Essaim cluster of satellites arrived in French Guiana aboard
an Air France Boeing 747 freighter aircraft. They were transferred from
Cayenne's Rochambeau International Airport to the Spaceport, where they are
now undergoing their checkout and pre-launch preparation process.

Flight 165 is one of two Ariane 5 missions currently in preparation at the
Spaceport. The other is Flight 164, which will use an Ariane 5 ECA to orbit
the XTAR-EUR governmental telecommunications satellite and an
experimental/test payload consisting of the Sloshsat mini satellite (which
is to be separated during the mission), and the Maqsat B2 telemetry/video
imaging package (which will remain mated to Ariane 5 throughout the
mission).